This story has everything: infidelity, sterilizing horseback riding injuries, passive-aggressive parenting...it's a fascinating crisis for everybody who isn't the kid.
The little boy's backstory is scandalous. The Not The Father wrote:
I (27M) used to have a wonderful relationship with the woman I love (26F). However, five years ago, she got drunk, had a one night stand, and got pregnant from it. Can't be mine, I can't have kids due to a horseback riding injury when I was a teen. Didn't get the guys name, no way to find him, so he's out of the picture. My wife decided to keep it, and we almost went through a divorce, but couples therapy made us decide to try again. We're still in therapy now, since I still have a hard time trusting her.